1. Field of the Invention
The present invention relates to a device for a wound wire that is relatively stiff such as electrical wires, cables or similar.
2. Brief Description of the Prior Art
It is common practice for shipping and handling purposes to wind wire or cable into spires forming torus shaped coils or rolls. These coils or rolls are later transported and eventually unwounded during installation of the wire by means of wire carts and dispensers such as those described and shown in U.S. Pat. Nos. 5,931,484; 5,996,930 and D409,897.
Coils and rolls of relatively stiff wire such as electrical cable, stay cable and triplex cable, are somewhat different. Since the spires forming these coils or rolls are made of relatively stiff material, they are characterized by a radial outward urge to unwind.
During shipping and handling, the coil of stiff wire is prevented from unwinding by a set of spaced straps disposed and tied around the spires. For the unwinding operation, the coil is positioned inside a unwinding reel such as the one described in Canadian patent No. 2,042,524. The straps are then removed and the spires located at the outer periphery of the coil resiliently abut against the walls of the reel which restrain their radial urge to unwind.
One of the main problems encountered with coil of stiff wire is that, since the coil does not rotate, the wire has a tendency to twist helically on itself as it is being pulled out the reel. The wire being relatively stiff it has a tendency to resiliently untwist. This situation thus creates a potential hazard for the person pulling on the coil as it is being unwounded.
To solve this problem, CA 2,042,524 provides an unwinding reel with a circular shield plate which function is to contain the wire inside the reel and thereby protect the person pulling on the coil as it is being unwounded. Although useful, the unwinding reel of patent CA 2,042,524 is relatively complex and cumbersome. Indeed, a user can not see very well how much wire there is left in the reel. Furthermore, the circular shield plate of CA 2,042,524 must be removed to install a coil of wire which cause a loss of time. The plate also add weight to the reel. The reel described in CA 2,042,524 also comprises a tubular cylindrical member devised to guide and frictionally hold the wire being pulled. However, this cylindrical tubular member has proven not be very functional.
There is thus a need for a lighter, more efficient, simpler to construct and more economical device for unwinding a coil of relatively stiff material, as compared to what is known in the art.
The present invention also fulfils other needs which will be apparent to those skilled in the art upon reading the following specification.
According to a first aspect of the invention, there is provided a device for a wound wire that is relatively stiff, which comprises:
a shaft;
a hub rotatively mounted around the shaft, the hub comprising a central core and a plurality of arms extending radially outwardly therefrom and at least partially around the wound wire for containing the wound wire and restraining an innermost spire thereof; and
guiding means connected to the shaft for guiding the wire extending from the innermost spire as a free end of the spire is being pulled.
Preferably, the device of the invention comprises at least five arms respectively terminated with U-shaped ends. The device may also comprises connecting means for releasably connecting at least some of the arms to the hub.
In another preferred embodiment, the device further comprises mounting means connected to the shaft for fixing the device to a structure.
According to another preferred embodiment, the device of the invention is provided with improved guiding means, the guiding means comprising a body provided with a conical bore having an inlet and an outlet that is smaller than the inlet. The outlet has an internal diameter slightly larger than that of the wire so that the body frictionally engages and holds the wire when it is released. More preferably the body is rigidly connected to the shaft and it is positioned as to be located slightly outside a vertical plane defined by the wound wire with an horizontal angle from about 15xc2x0 to 45xc2x0 with the vertical plane.
In yet another preferred embodiment, the hub comprises a circular disk extending radially outwardly from the central core, the arms being connected to the circular disk. More preferably, the circular disk comprises a plurality of solidifying ribs extending radially from the central core for solidifying the disk and rigidly connecting the disk to the central core.
According to a second aspect of the invention, there is provided a device for a wound wire that is relatively stiff, which comprises:
a shaft;
a body rotatively mounted on the shaft;
a hub mounted around the shaft, the hub comprising a central core and a plurality of arms extending radially outwardly therefrom and at least partially around the wound wire for containing the wound wire and restraining an innermost spire thereof; and
guiding means connected to the body for guiding the wire extending from the innermost spire as a free end of the spire is being pulled.
Other aspects and advantages of the present invention will be apparent from the following specification and the accompanying drawings which are for the purpose of illustration only.